Double bucket die cutting assembly

ABSTRACT

A double bucket die cutting assembly is provided which is particularly adaped to be installed at the die cutting station of a press for purposes primarily of accomplishing a punching operation thereat upon a moving web of material passing thereby. The double bucket die cutting assembly includes a frame structure in which a pair of buckets are mounted for eccentric rotation about a drive axis in suitably spaced relation relative to each other whereby to permit the material, upon which it is desired to perform a punching operation, to be passed therebetween. One of the buckets is provided with punch means suitably supported thereon so as to lie in a common plane extending the length of the major axis thereof. The other of the buckets is provided with receiving means operable to permit the punch means to be received therein as the punch means is brought into juxtaposed relation therewith during the rotation of the pair of buckets. The frame structure further includes counterbalancing means comprising a pair of weighted rollers which are supported in the frame structure for rotation relative thereto. Each of the rollers is provided with an irregular distribution of the weight thereof about its axis of rotation so that the heavy portion of the weighted rollers will be disposed to the opposite side of the center line from the buckets thereby providing a counterbalancing force to the weight of the buckets during the rotation of the latter. Alignment means are provided cooperatively associated with each of the pair of buckets so as to ensure that proper alignment between the pair of buckets is maintained during the rotation thereof. The frame structure also serves as a support for a drive means which is operable to drive each of the pair of buckets and each of the pair of weighted rollers so that they rotate in a predetermined fashion whereby to ensure that the pair of weighted rollers accomplish their intended counterbalancing function relative to the pair of buckets.

United States Patent [191 Kesten et al.

( 1 Jan. 21, 1975 DOUBLE BUCKET DIE CUTTING ASSEMBLY [75] Inventors:Martin Kesten, West Hartford;

Richard L. Edwards, Windsor Locks, both of Conn.

[73] Assignee: Preston Engravers, 1nc., Windsor.

Conn.

22 Filed: Nov. 16, 1973 21 Appl. No.: 416,663

Primary Examiner-Andrew R. Juhasz Assistant ExaminerW. R. Briggs [57]ABSTRACT A double bucket die cutting assembly is provided which isparticularly adaped to be installed at the die cutting station of apress for purposes primarily of accomplishing a punching operationthereat upon a moving web of material passing thereby. The double bucketdie cutting assembly includes a frame structure in which a pair ofbuckets are mounted for eccentric rotation about a drive axis insuitably spaced relation relative to each other whereby to permit thematerial, upon which it is desired to perform a punching opera tion, tobe passed therebetween. One of the buckets is provided with punch meanssuitably supported thereon so as to lie in a common plane extending thelength of the major axis thereof. The other of the buckets is providedwith receiving means operable to permit the punch means to be receivedtherein as the punch means is brought into juxtaposed relation therewithduring the rotation of the pair of buckets. The frame structure furtherincludes counterbalancing means comprising a pair of weighted rollerswhich are supported in the frame structure for rotation relativethereto. Each of the rollers is provided with an irregular distributionof the weight thereof about its axis of rotation so that the heavyportion of the weighted rollers will be disposed to the opposite side ofthe center line from the buckets thereby providing a counterbalancingforce to the weight of the buckets during the rotation of the latter.Alignment means are provided cooperatively associated with each ofthcpair of buck ets so as to ensure that proper alignment between the pairof buckets is maintained during the rotation thereof. The framestructure also serves as a support for a drive means which is operableto drive each of the pair of buckets and each of the pair of weightedrollers so that they rotate in a predetermined fashion whereby to ensurethat the pair of weighted rollers accomplish their intendedcounterbalancing function relative to the pair of buckets.

8 Claims. 6 Drawing Figures DOUBLE BUCKET DIE CUTTING ASSEMBLYBACKGROUND OF THE INVENTION There have long existed in the prior artmeans adapted to perform punching operations on a variety of differentkinds of material. Moreover, it has also long been known heretofore toprovide a press with a die cutting assembly capable of performing apunching operation. Based on experiences garnered from the use of suchprior art forms of devices, it has been learned that there are a numberof features which such devices desirably should possess if they are tooperate effectively yet still provide economies during manufacture andduring the operation thereof.

One particularly desirable feature which a die cutting assembly shouldpossess is that it be capable of a relatively high rate of speed inorder to produce a high rate of production, i.e., perform a large numberof operations per a given unit of time. In this connection, it has beenrecognized that one of the areas in which prior art devices have shown alimitation is in their speed of operation. More specifically, means havelong been available heretofore which are capable of feeding stock to adie cutting assembly at a relatively high rate of speed. Althoughimprovements have been made through the years in the design for diecutting assemblies in an effort to increase the speed of operationthereof such as, for example, by providing a die cutting assembly whichis capable of performing a punching operation on a moving web of stockmaterial, the speed at which even these latter forms of prior artdevices are capable of operating still remains less than the speed atwhich the stock material is capable of being fed thereto. Accordingly,there has existed a potential for achieving higher production rates byvirtue of providing a die cutting assembly which is capable of operatingat a speed corresponding to the optimum rate at which the stock materialis capable of being fed thereto.

Another feature which a die cutting assembly desirably should possess isthat of being capable of performing a series of operations in relativelyclosely spaced relation to each other on a web of material. Heretofore,the relatively large size of the operating components of the die cuttingassembly have commonly limited the capability of the latter assembly topermit repeat operations on shortened lengths of material travel. Inthis connection, it has been known to provide a plurality of closelyspaced die cutting means in one assembly in an effort to provide theaforedescribed capability. However, to do so increases the complexity ofthe assembly and concomitantly most often the cost of manufacture, andthe assembly thereof.

Accordingly, it is an object of the present invention to provide a noveland improved double bucket die cutting assembly which embodies aconstruction that enables an increase to be achieved in the speed withwhich operations are capable of being performed thereby.

It is also an object of the present invention to provide such a doublebucket die cutting assembly which permits repeat operations to beperformed in shortened lengths of stock travel.

It is a further object of the present invention to provide such a doublebucket die cutting assembly which is characterized by the fact that itis easily installable in conventional fashion in a press and occupiesonly limited space when mounted therein.

Still another object of the present invention is to provide such adouble bucket die cutting assembly which is capable of performingoperations on a continuously moving web of stock thereby enabling stockto be fed through the assembly at a relatively high rate of speed.

A still further object of the present invention is to provide such adouble bucket die cutting assembly which permits the buckets thereof tobe easily changed for purposes of altering the pattern produced therebyas a result of the operation thereof.

Yet another object of the present invention is to provide such a doublebucket die cutting assembly which produces during the operation thereofa definite penetration in the stock thereby to effectively separate thewaste from the latter stock.

SUMMARY OF THE INVENTION It has now been found that the foregoing andrelated objects can be readily attained in a double bucket die cuttingassembly which is operable when installed at the die station of a pressfor performing punching operations on a continuously moving web of stockbeing fed thereby.

The double bucket die cutting assembly includes a frame structure inwhich a pair of buckets are rotatably mounted in suitably spacedrelation relative to each other whereby to permit stock upon which it isdesired to perform a punching operation, to be passed therebe tween. Oneof the buckets is provided with punch means suitably supported thereonso as to lie in a common plane extending the length of the major axisthereof. The other of the buckets is provided with receiving meansoperable to permit the punch means to be received therein as the punchmeans is brought into juxtaposed relation therewith during the rotationof the pair of buckets. The frame structure further includes acounterbalancing means which is supported thereon for rotation relativethereto. The counterbalancing means is disposed to the opposite side ofthe center line from the buckets thereby providing a force which is effective to counterbalance the weight of the buckets during the rotationof the latter. Alignment means are provided cooperatively associatedwith each of the pair of buckets so as to ensure that proper alignmentbetween the pair of buckets is maintained during the rotation thereof.The frame structure also functions as a support for a drive means whichoperates to drive the pair of buckets and the counterbalancing means inunison so as to ensure that the counterbalancing means performs theproper counterbalancing function as the buckets rotate.

In accordance with the preferred embodiment of the invention, the doublebucket die cutting assembly includes a frame structure comprised of apair of elongated, suitably spaced frame members. Supported for rotationin the frame structure are a plurality of stub shafts. The pair ofbuckets are each mounted eccentrically on a corresponding pair of thesestub shafts such that the buckets are positioned between the framemembers and extend transversely substantially at right angles thereto.Alignment means preferably in the form of a plurality of pins arecooperatively associated with the pair of buckets. The pins function tointerconnect the pair of buckets whereby to ensure that a propercontinual alignment exists therebetween as the pair of buckets arecaused to rotate. A pair of weighted rollers are mounted for rotation onthe frame members, and are positioned so as to extend between the framemembers on either side of the buckets. Each of the weighted rollers hasthe weight thereof unequally distributed about its axis of rotation sothat the heavy portion of the weighted rollers is disposed to theopposite side of the center line from the buckets thereby providing acounterbalancing force to the weight of the buckets during rotation ofthe latter. Drive means operable to drive the pair of buckets and thepair of weighted rollers in unison are supported on the frame structure.The drive means preferably includes a plurality of interconnected gearswhich are respectively mounted on the pair of buckets and the pair ofweighted rollers.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational viewpartially in section and with some parts broken away for purposes ofclarity of illustration of a double bucket die cutting assemblyconstructed in accordance with the present invention;

FIG. 2 is a cross sectional view of the double bucket die cuttingassembly of the present invention taken sub stantially along the line 22in FIG. 1;

FIG. 3 is an end view of the left end of the double bucket die cuttingassembly of FIG. 1 constructed in accordance with the present invention;

FIG. 4 is an exploded perspective view of the pair of buckets and one ofthe pair of weighted rollers embodied in a double bucket die cuttingassembly constructed in accordance with the present invention;

FIG. 5 is a schematic representation of the movements during onerevolution of the pair of buckets and the pair of weighted rollers of adouble bucket die cutting assembly constructed in accordance with thepresent invention; and

FIG. 6 is a side elevational view partially in section of an overrideclutch for a double bucket die cutting assembly constructed inaccordance with the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Referring now to thedrawings and more particularly FIG. 1 thereof, there is illustratedtherein a double bucket die cutting assembly, generally designated byreference numeral 10, constructed in accordance with the presentinvention. The double bucket die cutting assembly 10 includes a framestructure 12 which is comprised of a pair of elongated substantiallyT-shaped frame members 14 and 16. The members 14 and 16 function as asupport means for the various elements which comprise the double bucketdie cutting assembly 10 including the punch bucket 18 and the die bucket20, and the pair of weighted rollers 22 and 24.

As best understood with reference to FIG. 4 of the drawings. each of thebuckets l8 and is generally rectangular in configuration and has asubstantially hollow interior. Projecting outwardly from each end ofeach of the buckets l8 and 20 is a pin-like shaped member 26 and 28,respectively. The latter members 26 and 28 are suitably dimensioned soas to be receiv' able in an opening 30 and 32, respectively, providedfor this purpose in one end of corresponding pairs of stub shafts 34 and36, respectively. In the interest of clarity of illustration, only oneof each of the corresponding pairs of shafts 34 and 36 has been depictedin FIG. 4 of the drawings. Each of the shafts 34 and 36 is formed withan enlarged portion 34a and 360. respectively, which contains theopenings 30 and 32 in which the pin-like members 26 and 28,respectively. are received. In addition, each of the shafts 34 and 36 isprovided with a smaller shaft-like portion 34b and 36h. respectively,the latter providing the means whereby the buckets I8 and 20 arerotatably mounted on the frame members I4 and 16 as will be describedmore fully hereinafter. Referring further to FIG. 4 ofthe drawings. itcan be seen therefrom that the openings 30 and 32 are located off centerrelative to the axis of rotation of the shafts 34 and 36. Accordingly,the buckets I8 and 20 when mounted to the shafts 34 and 36 are mountedeccentrically relative thereto whereby to provide a particular mode ofoperation for the assembly I0 to which further reference will be hadsubsequently. Although not shown in the drawings, it is to be understoodthat the punch bucket 18 is provided with a plurality of punches (notshown) which are suitably supported thereon so as to extendsubstantially the entire length of the major axis thereof. Similarly,the die bucket 20 is provided with cooperable die means 38 which areoperable to coact with the punches of punch bucket I8 so as to performthe desired punching operation on a web of stock as the latter passestherebetween. The die means 38 may take any suitable form such as. forexample. the form depicted in FIG. 4 of the drawings. i.e.. a pluralityof openings 40 which are formed in a plate 42 so as to be spacedrelative to each other therealong. and with the plate 42 extendingsubstantially the entire length of the major axis of the die bucket 20.The plate 42 may be affixed to the die bucket 20 through the use of anysuitable conventional fastening means.

Turning now to a description of the pair of weighted rollers 22 and 24,the latter as will be referred to more fully hereinafter during thecourse of the description of the mode of operation of the double bucketdie cutting assembly 10, function as a counterbalancing force for theweight of the buckets l8 and 20 as the latter are caused to rotate. Withreference to the weighted rollers 22 and 24, inasmuch as theconstruction of each of the rollers 22 and 24 is generally the same. thedescription thereof will be limited hereinafter to a description of theweighted roller 22 as shown in FIG. 4 of the drawings. The weightedroller 22 consists of a heavy portion 44 of cylindrical configurationwhich is eccentrically supported on a shaft 46 so as to be positioned atequal distances from the frame members l4 and 16. The eccentric mountingof the cylindrical portion thus provides an unequal distribution of theweight about the axis of rotation thereof. As such, end 460 of the shaft46 extends outwardly from the heavy portion 44 to a lesser distance thandoes the other end 46b of the shaft 46. The short end 460 of the shaft46 is suitably dimensioned so as to be receivable in an opening 48provided therefor in a plug bushing 50. Preferably, as shown in FIG. 4of the drawings, the short end 46a of the shaft 46 is provided with aslot 52 with is adapted to cooperate with a key 54. The key 54 which isillustrated in FIG. I of the drawings is received in the slot 52 whenthe short end 460 of shaft 46 is inserted into the open ing 48 andfunctions to securely interconnect the shaft 46 and thereby the weightedroller 22 at one end to the plug bushing 50. The other end 46b of theshaft 46 also has a slot 56 formed therein for a purpose yet to bedescribed. As can be seen from FIG. 1 of the drawings, the weightedroller 24 which is substantially identical in construction to theweighted roller 22 also consists of a heavy portion 58 which is providedon a shaft 60 so as to be equally spaced from the frame members 14 and16 thereof in the manner referred to hereinabove in connection with thedescription of the construction of weighted roller 22.

Referring now again to FIG. I of the drawings, with the end 46a of shaft46 inserted in opening 48 of the plug bushing 50, for purposes ofsupporting the weighted roller 22 on the frame structure 16 the smallerdiameter portion 50a of the plug bushing 50 is inserted into a bearing62 which is in turn positioned in an opening 64 provided for thispurpose in the frame member 16. The larger diameter portion 50b of theplug bushing 50 is received in similar fashion in a hearing 66. Thebearing 66 has a lesser length than does the portion 50b of plug bushing50 whereby to enable a gear 68 to be positioned between the end ofbearing 66 and the shoulder provided between the portions 50a and 50b ofthe bushing 50. The opening provided in the bearings 62 and 66 toreceive plug bushing 50 is suitably dimensioned to enable the gear 68 tobe received therein so as to be capable of rotation relative thereto.For purposes of maintaining the gear 68 properly aligned on the portion50b of plug bushing 50, the gear 68 is preferably provided with a key 70which is adapted to be received in a slot (not shown) formed for thispurpose in the portion 50b.

With further reference to FIG. I of the drawings, it can be seentherefrom that the longer end 46b of weighted roller 22 is of sufficientlength to pass through and extend outwardly of a bearing 72 which ispositioned in an opening 74 provided for this purpose in the framemember 14. A gear 76 is preferably affixed to the end 46b by means of akey (not shown) which is received in the slot 56 to which reference washad previously hereinabove. The opening 74 provided in the frame member14 is suitably dimensioned so as to permit the gear 76 to be receivedtherein and to be rotat able relative thereto. A second gear 78 to whichfurther reference will be had hereinafter is suitably mounted such as bybeing keyed thereto at the tip of the longer end 46b so as to rotatewith the shaft 46.

Although not specifically depicted in the drawings. it is to beunderstood that the weighted roller 24 is supported on the frame members14 and 16 so as to extend therebetween substantially at right anglesthereto in the same manner as has been set forth hereinabove inconnection with the description of the manner in which the weightedroller 22 is mounted. Namely. both short ends 60a and 60b of the shaft60 of the weighted roller 24 are inserted into plug bushings (not shown)similar in construction to the plug bushing 50. With the shaft end 600so mounted in the plug bushing. the latter in turn is inserted in anopening (not shown) provided for this purpose in the frame member 16.The end 600 of shaft 60 also has a gear (not shown). which is similar inc'onstruction to the gear 68, supported thereon so as to be rotatabletherewith. The other end 60b of the shaft 60 mounts into a bearing (notshown) which is provided in an opening (not shown) provided therefor inthe frame member 14. Also. there is mounted a gear 80 which is similarin construction to the previously described gear 68 which is mounted onthe shaft end 46a.

With regard to the manner in which the buckets l8 and 20 are supportedon the frame members I4 and [6, this is accomplished in a manner similarto the way the short shaft ends 46a and 60a of weighted rollers 22 and24, respectively. are mounted on the frame member [6. More particularly.as was described previously hereinabove. the pin-like members 26 ofpunch bucket 18 are mounted in a corresponding pair of stub shafts 34.only one of which is illustrated in FIG. 4. and the pin like members 28of die bucket 20 are mounted in a corresponding pair of stub shafts 36.only one of which is shown in FIG. 4. Each of the pair of stub shafts 34is positioned in an opening (not shown) provided therefor in acorresponding one of the frame members 14 and I6. In similar fashion,the pair of stub shafts 36 are each positioned in an opening (not shown)also provided therefore in a corresponding one of the frame members I4and 16. Thus. with the stub shafts 34 and 36 supported in theaforedescribed tnanner in the frame members 14 and 16, and with thepin-like members 26 and 28 inserted in the openings 30 and 32,respectively. provided for this purpose in the stub shafts 34 and 36,the buckets I8 and 20 are positioned so as to extend between andsubstantially at right angles to the frame members 14 and 16, asdepicted in FIG. I of the drawings. The openings (not shown) formed inthe frame members 14 and 16 in which the stub shafts 34 and 36 areinserted are suitably located along the length of each of the framemembers 14 and I6 so that the buckets l8 and 20 are capable. as will bereferred to more fully hereinafter to move in a vertical plane as viewedwith reference to FIG. 1 relative to the weighted rollers 22 and 24.respectively. as the buckets l8 and 20 rotate through one completerevolution. In accord with the preferred embodiment of the invention.the stub shafts 34 and 36 which are supported in the frame member 16 areeach provided with a gear (not shown) which is similar in constructionto the gear 68 which is affixed to the plug bushing 50. These gears aresuitably affixed, such as by being keyed thereto, to the larger diameterportions 340 and 36a of the stub shafts 34 and 36. respectively.Similarly. each of the stub shafts 34 and 36 which are supported in theframe member 14 have mounted thereon a gear 84 and 86, respectively,which is similar in construction to the gear 68 which is affixed to theshaft end 460 of weighted roller 22. Accordingly. the openings (notshown) which are provided in the frame members l4 and I6 and in whichthe stub shafts 34 and 36 are supported are also suitably locatedtherein so that the gears (not shown) which are affixed to the stubshafts 34 and 36 which are supported in frame member 16 are capable ofmeshing with the gear 68 supported on the plug bushing and with the gear(not shown) which is supported on the plug bushing (not shown) in whichthe shaft end 600 of weighted roller 24 is supported and so that thegears 84 and 86 which are affixed to each of the other stub shafts 34and 36 which are supported on the frame member 14 are capable of meshingwith the gear 76 and with the gear 80 which is affixed to the shaft endb of weighted roller 24.

Referring again to FIG. I of the drawings. the power by which therotation of the buckets l8 and 20 and the weighted rollers 22 and 24 isaccomplished. is derived from the drive of the press. etc., (not shown)in which the double bucket die cutting assembly [0 of the presentinvention is embodied. To this end. the double bucket die cuttingassembly 10 is provided with a drive means 88 which is supported on theframe structure 12 and is capable of being operatively connected to thedrive of the press, etc. As shown in FIG. I, drive in accord with theillustrated embodiment of the invention is imparted from the press, etc.through shaft 90 and a gear 92 supported thereon so as to be rotatabletherewith to a gear 94 which is affixed to the shaft 96 so as to rotatetherewith. One end of the shaft 96 is supported for rotation in asuitable bearing provided there for in the frame member I6 while theother end of shaft 96 passes through and extends outwardly of a bearing98 which is suitably positioned in an opening provided for this purposein the frame member 14. The latter end of the shaft 96 has a gear 82supported thereon for rotation therewith. The gear 82 in turn mesheswith a gear I00 which is carried on a shaft 102 which is supported onthe frame member I4 so as to be rotatable relative thereto. There isalso supported on the shaft I02, a second gear 104 and a wheel 106, thelatter being provided for a purpose which will be referred tosubsequently. In accord with the illustrated embodi ment, gears 100 and104 are further interconnected by pin means I08 suitably received inopenings (not shown) provided therefor in the gears 100 and 104.

Turning now to a description of the mode of opera tion of the doublebucket die cutting assembly 10, the shaft 96 is caused to rotate byvirtue of the drive which is imparted thereto from the press, etc.,through the shaft 90 and gears 92 and 94. As the shaft 96 rotates, thegear 82 carried thereby also rotates thereby causing gear 100 to alsorotate. The rotation which is imparted to the gear I00 is alsotransmitted primarily through shaft I02 to the gear 104 and therefrom tothe gear 78. Since gear 78 is affixed to the shaft 46 for rotationtherewith, as the gear 78 rotates the shaft 46 is also caused to rotate.When the shaft 46 rotates, the rotation thereof is transmitted throughgear 76 to the gears 84, 86 and 80 by virtue of the interconnectionwhich exists therebetween as depicted in FIG. 2 of the drawings. Insimilar fashion, rotation of shaft 46 also causes gear 68 to rotate andthe latter in turn transmits its rotation to the gears (not shown) whichare supported in frame member 16 on the ends of the stub shafts 34 and36 and the plug bushing (not shown) in which the shaft end 60a of theweighted roller 24 is mounted. Thus, it can be seen that the drive fromthe press, etc., is effective to cause the buckets l8 and 20 and theweighted rollers 22 and 24 to rotate in unison as a result of therotation of the plurality of gears which the buckets l8 and 20 and theweighted rollers 22 and 24 are interconnected.

As the buckets l8 and 20 rotate between a closed position, defining awork station i.e., the position thereof which is illustrated in FIG. 1of the drawings, and an open position wherein the buckets 18 and 20 arespaced relatively far apart, a continuous web 110 of stock material iscontinually being fed therebetween by suitable press means (not shown).When the buckets I8 and 20 occupy their closed position, the punches(not shown) supported on the punch bucket I8 penetrate the web 110thereby providing the latter with one or more perforations. Thus, a workoperation which may, as described hereinabove by way of illustration,take the form ofa punching operation, is performed on the web 110 duringeach complete revolution of the buckets l8 and 20.

In connection with the feeding of the web IIO to the assembly [0, it hasbeen found desirable to mount a pair of rollers I12 adjacent to theentrance and exit end of the assembly I0 suitably positioned so that theweb travels over the rollers 112. A pair of brackets H4 and 116 whichare fastened to the frame members [4 and 16, respectively, by means ofconventional fasteners II8 are employed for purposes of supporting eachroller II2 on the assembly I0. More specifically, the opposite ends ofthe roller II2 are inserted into the brackets 114 and 116, and are heldtherein by any suit able means such as by means of a plurality of setscrews I20.

Obviously, it is important in order to accomplish the desired workoperation that the punch bucket I8 and the die bucket 20 remaincontinually in proper alignment relative to each other they are causedto rotate. Therefore. in accord with the preferred embodiment of theinvention, the double bucket die cutting assembly 10 is provided with analignment means 122. The align ment means consists of a pair of pins 124and a plurality of brackets 126. The latter brackets I26 as best seen inFIG. I of the drawings are secured to the frame members 14 and I6 bysuitable fasteners I28 so as to be located between the weighted rollers22 and 24, and slightly spaced from the shafts 46 and 60 thereof. Thepins I24 are positioned in openings and I32 provided for this purpose indiagonally opposite corners of the buckets l8 and 20, respectively. Asdepicted in FIG. 4 of the drawings in connection with the illustra tionthereof ofthe bucket 18, openings 130 and I32 are preferably provided inbearings 134 with each of the openings 130 and 132 in buckets I8 and 20in align ment with each other. Each of the pins I24 is suitablydimensioned so that the length thereof is such that when the pins 124are positioned in the openings 130 and 132 in the buckets I8 and 20 andthe latter buckets I8 and 20 are supported between the frame members 14and 16 as shown in FIG. I of the drawings, the tips of the pins 124 arein engagement with a corresponding pair of the plurality of bracketsI26, and allowed to move in a horizontal direction from the rotation ofstub shafts 34 and 36. The pins 124 function to interconnect the bucketsl8 and 20 so as to ensure the continual proper alignment thereof as thebuckets I8 and 20 are caused to rotate while yet permitting verticalmovement of the buckets I8 and 20 along the pins I24.

If so desired, the double bucket die cutting assembly 10 may be providedwith an override clutch means I36 which is operable to permit slippageto occur between the drive being imparted from the press to the drivemeans 88 of the assembly 10 in the event that a malfunction should occurin the operation of the assembly 10 thereby to prevent damage being doneto any of the components of the latter. In accord with the preferredemployment thereof, the clutch means I36 is mounted on the end of shaft96 and is operable to cause slippage between the shaft 96 and the gear82. As best understood with reference to FIG. 6 of the drawings, theclutch means 136 includes a bushing I38 which is interposed between theshaft 96 and the gear 82. The latter bushing 138 is provided with acutout portion 140 to which further reference will be had hereinafter.In addition, the gear 82 has a radially extending opening I44 formedtherein which is threaded so as to be capable of receiving the set screwI42 therein, the latter set screw I42 being threaded in the opening 144into engagement with the cutout surface 140 of the bushing 138. Asfurther shown in FIG. 6, an opening 146 is provided through the bushing138, and the shaft 96. Inserted in the opening 146 is a spring 148 whichis employed to bias a cap 150 outwardly into engagement with the innersurface of the gear 82. The method of operation of clutch means 136 issuch that during normal operation of the assembly 10, when the shaft 96is rotated, the spring biased cap 150 is rotated into engagement withthe set screw 142 and bears thereagainst causing the rotation of theshaft 96 to be transmitted therethrough to the gear 82. However, in theevent that a blockage or some other form of malfunction should occurcausing the gear 82 to seek to resist the imparting thereto of arotational movement, as the shaft 96 con tinues to rotate the springbiased cap 150 is biased in wardly against the bias of the spring 148into the opening 146 by the set screw 142 thereby permitting the shaft96 to rotate past the set screw 142 and thereby providing slippagebetween the shaft 96 and the gear 82.

Referring now to FIG. of the drawings, the manner in which the weightedrollers 22 and 24 function to provide a counterbalancing force to theweight of the buckets 18 and during the rotation thereof is most clearlyunderstood with reference to the illustrations in FIG. 5 of thesequential movements which the buckets l8 and 20 and the weightedrollers 22 and 24 undergo during one complete revolution. Beginning atthe left side of FIG. 5, the positions in which the buckets l8 and 20and the weighted rollers 22 and 24 are shown correspond to the closedposition of the buckets 18 and 20 wherein work is being performedthereby on the web 110, i.e., the positions thereof shown in FIG. I ofthe drawings. It can thus be seen that in this first position the heavyportions 44 and S8 of the weighted rollers 22 and 24, respectively,provided by the eccentric mounting of the cylindrical portions arelocated relative to the buckets l8 and 20 whereby the rollers 22 and 24operate to balance the vertical weight of the buckets 20 and 18,respectively. In the second position thereof shown in FIG. 5, as thebuckets I8 and 20 begin moving in opposite rotations thereby to create aspace therebetween, the weighted roller 22 rotates in a directionopposite to the direction of rotation of the bucket 18 while theweighted roller 24 is being rotated in a direction opposite to thedirection of rotation of bucket 20. Accordingly, the heavy portion 44 ofweighted roller 22 counterbalances the horizontal weight of the bucket18 and the heavy portion 58 of weighted roller 24 functions as acounterbalancing force to the horizontal weight of the bucket 20 as thelatter rotates. In the middle position depicted in FIG. 5, the heavyportion 44 of weighted roller 22 has been rotated to a position where itis effective to balance with the weight of the bucket 20 while the heavyportion 58 of weighted roller 24 is located so as to be in a positionwhere it is operable to balance with the weight of the bucket 18. In thefourth position thereof shown in FIG. 5 of the drawings, the heavyportion 44 of the weighted roller 22 has continued its rotation so thatit now occupies a position wherein it is capable of balancing the weightof the bucket 18 and the heavy portion 58 of weighted roller 24 has beenrotated so that is located in a position wherein it is effective tobalance the weight of the bucket 20. The positions of the weightedrollers 22 and 24 and the buckets l8 and 20 shown at the extreme rightof FIG. 5 are the same as those shown at the extreme left of FIG. 5 andare presented for purposes of depicting the completion of a full 360revolution of these elementsv Thus, it should be clear with reference tothe preceding description that the weighted rollers 22 and 24 co-actwith the buckets l8 and 20 so that the former are continually able toprovide a counterbalancing force to the forces being generated by theweight of the buckets l8 and 20 as the shafts 34 and 36 on which thebuckets I8 and 20 are mounted are rotated.

In accord with the illustrated embodiment of the invention, the doublebucket die cutting assembly 10 is preferably provided with a wheel 106which when rotated is operable to cause the gears 104 and 106 to rotate.The rotation of the latter gears 104 and I06 is ef fective to also causethe buckets l8 and 20 and the weighted rollers 22 and 24 to be rotatedthrough operation of the drive means 88. The purpose of providing theassembly l0 with this manual capability to rotate the buckets 18 and 20and the weighted rollers 22 and 24 is that is has been found that onoccasions the buckets 18 and 20 and the weighted rollers 22 and 24 maybe stopped in such a position that they bear a relationship to eachother wherein the inertia needed to be overcome in order to cause themto begin rotating once again is substantial. Accordingly, when thiscondition is found to exist, it is possible through operation of thewheel 106 to rotate the buckets l8 and 20 and the weighted rollers 22and 24 to a position wherein the re lationship which they bear to eachother is such that less inertia is required to be overcome for therotation of the shaft 96 to be transmitted thereto. The construction ofthe double bucket die cutting assembly 10 as illustrated in the drawingsand as described hereinabove provides the assembly 10 with a number ofdesirable features. In this regard, the assembly 10 is constructed so asto be capable of fitting as a complete unit into a die station of apress. This renders it unnecessary to provide additional lengths of webmaterial to be utilized for purposes of threading the web material intothe assembly 10 or for tensioning the web material and as such alsoobviates the problems involving registration occasioned thereby. Also,since the assembly 10 is being driven directly as a die would be, thisalso mini mizes the problem of achieving registration between the web110 of stock material and the punch bucket 18 and die bucket 20. Anotherdesirable feature possessed by the assembly 10 is that by virtue of theuse therein of buckets for purposes of securing the punches and diemeans therein, it is relatively easy to change both ofthc latter. Thus,ifit is desired to change the pattern of the hole being punched byreplacing the punch and die sets being used, this is easily accomplishedmerely by changing the buckets. The alignment means 122 with which theassembly 10 is provided also provides the latter with another desirablefeature, namely, that by vir tue of the constant alignment which iscapable of being achieved thereby, it is possible to provide virtuallyzero clearance between mating edges of the punch (not shown) and the dieholes 40 thereby obtaining clear. fiberfree holes in the web of stockmaterial. In the event it is desired to change the spacing by which repeat operations are performed on the web, there is embodied in theassembly 10 structure which permits this to be done simply by making twosimple changes therein, namely, to change gears in the drive means 88and the location of openings 26 and 28 in stub shafts 34 and 36,respectively. Finally, the double bucket die cutting assembly 10 of thepresent invention possesses the advantages of both linear and rotarymotion. The advantage of rotary motion is the fact that the web enablesthe user to operate at a high degree of speed. The advantage of linearmotion in the field of punch and die work is the fact that the waste isdefinitely removed from the web, i.e., there is no chance of waste beingleft in a cavity as often occurs when employing prior art devices. Ashigh speeds are constantly being demanded by today's technology, greateris the requirement for balancing the moving parts of the device. In theassembly 10, the weight of the heavy portions 44 and 58 of the weightedrollers 22 and 24 can be calculated very precisely and the rollers 22and 24 can be sized with as great an accuracy as is needed. Yet therollers 22 and 2.4 can easily be changed to meet any change in jobrequirements, namely, a change in repeat and/or punch mass.

Although only one embodiment of a double bucket die cutting assemblyconstructed in accordance with the present invention has been shown inthe drawings and described hereinabove, it is to be understood thatmodifications in the construction thereof may be made thereto by thoseskilled in the art without departing from the essence of the invention.In this connection, some of the modifications which can be made in thedouble bucket die cutting assembly 10 have been alluded to hereinabovewhile others will become readily apparent to those skilled in the artwhen exposed to the present description and illustration of theconstruction of the assembly 10. For example, though the assembly 10 hasbeen described hereinabove as preferably being employed to performpunching operations such as punching small holes or long skinny holes,etc., in a continuously moving web of stock material, the assembly I isalso capable of being employed to perform a variety of other forms ofwork operations. Thus, by replacing the punches supported on punchbucket 18 and the die means 38 on die bucket 20 with other suitabletypes of work performing means, the assembly is capable of beingemployed to perform other work operations such as to apply paperreinforcements, to provide successive numbering, to do deep-setembossing, to string tags, to encapsulate items under a bubble, to applyheated plastic over dispenser items, etc. More' over, though it has beenfound preferable to interconnect each end of the weighted rollers 22 and24 and the buckets l8 and together through gears in order to resist thetorques generated during the rotation of the rollers 22 and 24 and thebuckets l8 and 20, the gears which are supported for rotation in theframe member 16 may be omitted if so desired with some other form ofmeans being utilized to resist the forces caused by the aforereferencedtorques.

Thus, it can be seen that the present invention provides a novel andimproved double bucket die cutting assembly which embodies aconstruction that enables an increase to be achieved in the speed withwhich operations are capable of being performed thereby. Moreover, thedouble bucket die cutting assembly of the present invention permitsrepeat operations to be performed in shortened lengths of stock travel.Furthermore, in accord with the present invention a double bucket diecutting assembly has been provided which is characterized by the factthat it is easily installed in conventional fashion in a press andoccupies only limited space when mounted therein. The double bucket diecutting assembly of the present invention is capable of performingoperations on a continuously moving web of stock thereby enabling stockto be fed through the assembly at a relatively high rate of speed. Also,in accord with the present invention a double bucket die cuttingassembly has been provided which permits the buckets therein to beeasily changed for purposes of altering the pattern produced by theassentbly as a result of the operation thereof. Finally, the doublebucket die cutting assembly of the present invention produces during theoperation thereof a definite penetration in the stock thereby toeffectively separate the waste from the latter stock.

Having thus described the invention, we claim:

1. A double bucket die cutting assembly, operable to perform a workoperation on a length of material, comprising:

a. frame means including a pair of frame members;

b. bucket means mounted on said pair of frame mem bers including firstand second buckets having cooperating work performing means supportedthereon, said bucket means also including first and second support meansrotatably mounted on said frame and having the ends of said bucketseccentrically supported thereon for movement of said buckets to and froma closely spaced work performing position in which said work performingmeans cooperate to perform a work operation on a length of materialpassing therebetween, said work performing position of said bucketsdefining a work station;

c. counterbalancing means movably mounted on said pair of frame membersoperable to counterbalance the weight of said first and second buckets,said counterbalancing means including first and second rollers extendingtransversely between said frame members in spaced relation to said firstand second buckets and on opposite sides of the plane defining said workstation, and support means rotatably mounting said rollers on said framefor rotation about an axis substantially in the same plane as the axesof rotation of said buckets, said rollers having the weight thereofunequally distributed about their axes of rotation; and

d. drive means supported on said pair of frame members and operativelyconnected to said bucket means and said counterbalancing means fordriving said first and second buckets to and from said work performingposition and for moving said counterbalancing means in a predeterminedmanner to relative to said first and second buckets to cause saidcounterbalancing means to produce a firce effective to counterbalancethe force produced by the weight of said first and second buckets duringthe movement thereof to and from said work performing position.

2. The double bucket die cutting assembly as set forth in claim 1further comprising alignment means supported on said bucket meansincluding a pair of pins interconnecting said first and second bucketsoperable for maintaining the proper alignment between said first andsecond buckets during the movement thereof.

3. The double bucket die cutting assembly as set gorth in claim 1wherein said drive means includes a first set ofgears interconnectingone end of each of said first and second buckets and said first andsecond rollers, and a second set of gears interconnecting the other endof each of said first and second buckets and said first and secondrollers.

4. The double bucket die cutting assembly as set forth in claim 3further comprising override clutch means supported on said frame meansoperatively connected toi said drive means to permit said drive means toslip during a malfunction of the assembly.

5. The double bucket die cutting assembly as set forth in claim 1wherein said first and second rollers each comprise a shaft having acylindrical element eccentrically supported thereon.

6. A double bucket die cutting assembly, operable to perform a punchingoperation on a continuous web of material, comprising:

a. frame means including a pair of frame members;

b. bucket means including first and second buckets and first and secondsupport means rotatably mounted on said frame and having said first andsecond buckets supported eccentrically thereon to permit said first andsecond buckets to undergo both linear and rotational motion in moving toand from a closely spaced work performing position, said first andsecond buckets having cooperating work performing means supportedthereon operable to perform a punching operation on a continuous web ofmaterial passing therebetween when said first and second buckets are atsaid work per forming position defining a work station;

c. counterbalancing means movably mounted on said frame means includingfirst and second rollers extending transversely between said framemembers and support means rotatably mounting said first and secoindrollers on said frame means on opposite sides of the plane defining saidwork station in spaced relation to said first and secoind buckets, saidsupport means rotatably mounting said rollers for rotation about axessubstantially in the same plane as the axes of said rotation of saidbuckets, said rollers having the weight thereof unequally distributedabout their axes of rotation, the orientation of the heavier weightportion of the rollers relative to the cooperating buckets beingadjusted and operable to counterbalance the weight of said first andsecond buckets during the rotation thereof; and

d. drive means supported on said pair of frame mcm bers and operativelyconnected to said bucket means and said counterbalancing means fordriving said first and second buckets to and from said work performingposition and for moving said first and second weighted rollers in apredetermined manner relative to said first and second buckets to causesaid counterbalancing means to produce a force effective tocounterbalance the force produced by the weight of said first and secondbuckets during the movement thereof to and from said work performingposition.

7. The double bucket die cutting assembly as set forth in claim 6wherein said first and second rollers each comprise a shaft having acylindrical element eccentrically supported thereon.

8. the double bucket die cutting assembly as set forth in claim 6further comprising alignment means supported on said bucket meansincluding a pair of pins interconnecting said first and second bucketsoperable for maintaining the proper alignment between said first andsecond buckets during the movement thereof

1. A double bucket die cutting assembly, operable to perform a workoperation on a length of material, comprising: a. frame means includinga pair of frame members; b. bucket means mounted on said pair of framemembers including first and second buckets having cooperating workperforming means supported thereon, said bucket means also includingfirst and second support means rotatably mounted on said frame andhaving the ends of said buckets eccentrically supported thereon formovement of said buckets to and from a closely spaced work performingposition in which said work performing means cooperate to perform a workoperation on a length of material passing therebetween, said workperforming position of said buckets defining a work station; c.counterbalancing means movably muonted on said pair of frame membersoperable to counterbalance the weight of said first and second buckets,said counterbalancing means including first and second rollers extendingtransversely between said frame members in spaced relation to said firstand second buckets and on opposite sides of the plane defining said workstation, and support means rotatably mounting said rollers on said framefor rotation about an axis substantially in the same plane as the axesof rotation of said buckets, said rollers having the weight thereofunequally distributed about their axes of rotation; and d. drive meanssupported on said pair of frame members and operatively connected tosaid bucket means and said counterbalancing means for driving said firstand second buckets to and from said work performing position and formoving said counterbalancing means in a predetermined manner to relativeto said first and second buckets to cause said counterbalancing means toproduce a firce effective to counterbalance the force produced by theweight of said first and second buckets during the movement thereof toand from said work performing position.
 2. The double bucKet die cuttingassembly as set forth in claim 1 further comprising alignment meanssupported on said bucket means including a pair of pins interconnectingsaid first and second buckets operable for maintaining the properalignment between said first and second buckets during the movementthereof.
 3. The double bucket die cutting assembly as set gorth in claim1 wherein said drive means includes a first set of gears interconnectingone end of each of said first and second buckets and said first andsecond rollers, and a second set of gears interconnecting the other endof each of said first and second buckets and said first and secondrollers.
 4. The double bucket die cutting assembly as set forth in claim3 further comprising override clutch means supported on said frame meansoperatively connected toi said drive means to permit said drive means toslip during a malfunction of the assembly.
 5. The double bucket diecutting assembly as set forth in claim 1 wherein said first and secondrollers each comprise a shaft having a cylindrical element eccentricallysupported thereon.
 6. A double bucket die cutting assembly, operable toperform a punching operation on a continuous web of material,comprising: a. frame means including a pair of frame members; b. bucketmeans including first and second buckets and first and second supportmeans rotatably mounted on said frame and having said first and secondbuckets supported eccentrically thereon to permit said first and secondbuckets to undergo both linear and rotational motion in moving to andfrom a closely spaced work performing position, said first and secondbuckets having cooperating work performing means supported thereonoperable to perform a punching operation on a continuous web of materialpassing therebetween when said first and second buckets are at said workperforming position defining a work station; c. counterbalancing meansmovably mounted on said frame means including first and second rollersextending transversely between said frame members and support meansrotatably mounting said first and secoind rollers on said frame means onopposite sides of the plane defining said work station in spacedrelation to said first and secoind buckets, said support means rotatablymounting said rollers for rotation about axes substantially in the sameplane as the axes of said rotation of said buckets, said rollers havingthe weight thereof unequally distributed about their axes of rotation,the orientation of the heavier weight portion of the rollers relative tothe cooperating buckets being adjusted and operable to counterbalancethe weight of said first and second buckets during the rotation thereof;and d. drive means supported on said pair of frame members andoperatively connected to said bucket means and said counterbalancingmeans for driving said first and second buckets to and from said workperforming position and for moving said first and second weightedrollers in a predetermined manner relative to said first and secondbuckets to cause said counterbalancing means to produce a forceeffective to counterbalance the force produced by the weight of saidfirst and second buckets during the movement thereof to and from saidwork performing position.
 7. The double bucket die cutting assembly asset forth in claim 6 wherein said first and second rollers each comprisea shaft having a cylindrical element eccentrically supported thereon. 8.the double bucket die cutting assembly as set forth in claim 6 furthercomprising alignment means supported on said bucket means including apair of pins interconnecting said first and second buckets operable formaintaining the proper alignment between said first and second bucketsduring the movement thereof.